!+

subroutine ramp_function (t,frac_ref, extract_qv, extract_qh, extract_s, extract_octk3, bump)

use bmad
use ramp_parameters
use multibunch_interface

implicit none

logical err_flag

character(*), parameter :: r_name = 'track1_preprocess'
real(rp) t, frac_ref, f_AC/60./, extract_qv, extract_qh, extract_s, extract_octk3

real(rp) sint,w
real(rp) tau/2.52131e-6/
real(rp) turn_on
real(rp) bump
!
integer n, j, jmax, i, ix_corner(0:100)
integer turn
logical first/.true./

frac_ref = (-cos(twopi*f_ac * t) + 1.)/2. 

sint=0.
if(t>t_ext .and. t < 3*t_ext)then
  w = twopi*60.
!  do n=1,59,2
!   sint = sint + 1/float(n) * sin(n*w*(t-t_ext))
!  end do
! turn_on_time (time to turn on) in fractions of t_ext. If turn_on_time = 1/4, then sint goes from 0 to 1 in 1/4 t_ext after t_ext
if(t>t_ext .and. t< (1.+turn_on_time*t_ext))sint = (t-t_ext)/(turn_on_time*t_ext)
if(t>=(1.+turn_on_time)*t_ext)sint = 1.
endif

if(first)then ! assemble function for octupole
 print *,' size(oct_ramp) = ', size(oct_ramp)
 call create_profile(oct_ramp)
 call create_profile(quad_ramp)
 call create_profile(bump_ramp)
 call create_profile(sext_ramp)
 first=.false.
endif

   turn = min(size(oct_ramp)-1,int((t-t0)/tau))

   turn_on = 0.
   if(t>t_ext)turn_on=1
!   extract_qv = qv*sint
!   extract_qh = qh*sint
   extract_qv = qv*quad_ramp(turn)
   extract_qh = qh*quad_ramp(turn)
!   extract_octk3 =  octk3 * ext_param * max(0._rp, min(t,t1)-t_ext)  !+octk3*frac_ref * turn_on
   extract_octk3 =  octk3 * oct_ramp(turn)
!   bump = frac_ref * bump_ramp(turn)
   bump = bump_ramp(turn)
   extract_s = sextk2 * sext_ramp(turn)
!   if(t>t_ext)write(19,'(4es12.4)')t,t/tau,extract_s, extract_octk3
err_flag = .false.

end subroutine



!subroutine to create ramp profile P(turn) based on P specified at a few points 
subroutine create_profile(Q)
use bmad

implicit none

real(rp) Q(0:7000)
logical err_flag

real(rp) P_corner(0:100), slope

!
integer n, j, jmax/1/, i, ix_corner(0:100)
integer turn

character(len=32):: fmt

 !populate array P(1:nturns) based on corner values
  Q(0) = 0
  P_corner(0) = 0
  ix_corner(0) = 0
  j=0
  do i=1,size(Q)-1
   if(Q(i)>=0)then
     j=j+1
     P_corner(j) = Q(i)
     ix_corner(j) = i
     jmax = j
   endif
  end do
 print '(a,1x,10es12.4)',' P_corner', P_corner(1:min(10,jmax))
 if(jmax > 10)then
   write(fmt,'(a6,i2,a7)')'(a,1x,',jmax-10,'es12.4)'
!   print *, 'fmt = ', fmt
   print fmt,'        ',P_corner(11:jmax)
 endif
 print '(a,1x,10i10)', ' ix_corner ',ix_corner(1:min(10,jmax))
 if(jmax > 10)then
   write(fmt,'(a6,i2,a4)')'(a,1x,',jmax-10,'i10)'
   print fmt, '           ',ix_corner(11:jmax)
 endif

  do j=0,jmax-1
   slope = (Q(ix_corner(j+1)) - Q(ix_corner(j)))/(ix_corner(j+1)-ix_corner(j))
   do i = ix_corner(j)+1,ix_corner(j+1)-1
     Q(i) = slope * (i-ix_corner(j)) + Q(ix_corner(j))
   end do
  end do
! do i=0,size(Q)-1
!  print '(i10,1x,es12.4)', i,Q(i)
! end do
return
end